docs: def rectangle_centroid(rectangle):
      """
      get the centroid of the rectangle
  
      Keyword arguments:
      rectangle  -- polygon geojson object
  
      return centroid
      """
      bbox = rectangle['coordinates'][0]
      xmin = bbox[0][0]
      ymin = bbox[0][1]
      xmax = bbox[2][0]
      ymax = bbox[2][1]
      xwidth = xmax - xmin
      ywidth = ymax - ymin
      return {'type': 'Point', 'coordinates': [xmin + xwidth / 2, ymin + ywidth / 2]}